This invention pertains to the field of graduated measuring devices and, more particularly, to measuring tapes used to measure distances.
Measuring tapes are well known in the art, and are used to measure a distance between objects, a distance from a known point, or the length of an object. Measuring tapes are linear measuring devices which include a graduated steel tape blade for measuring a distance, typically up to 300 feet. Most prior art measuring tapes are comprised of a metal tape blade which is scaled in units of measure such as the foot or yard having the base 12 or 10, or the meter based on the metric system having the base 10; a case having a retraction system to retract the tape blade into the case and to provide a means for compact storage of the tape when not in use; and a stop at the end of the tape which is used to anchor the tape when measuring a length or distance and which prevents the tape from fully retracting into the case. Graduated measuring devices also include rulers, collapsible tapes, steels, manual tape measures, woven tapes, and protractors, or circular measuring devices.
Prior art measuring tapes are limited in that they have graduations equal to the length of the tape blade and thus can only measure a distance equal to the length of the tape blade. Although the measuring tape can be used to measure a distance longer than the actual tape length by making a second measurement in series with the first, this requires that the user add the first measurement to the second measurement to determine the total measured distance. This addition may be performed mentally or may require recording the measurements for addition. The manual recording of measurements for addition is inconvenient since it requires putting down the measuring tape, locating a writing utensil and paper, recording the multiple measurements, and then adding the measurements. Such calculations may lead to errors in addition.
The present invention includes a continuous graduated measuring tape capable of measuring a distance greater than its length to overcome these deficiencies of the prior art. Other objects and advantages of the present invention will become apparent from the following description.